Ask HN: What are the most popular or up-and-coming tech buzz words?

And are they actually buzz words or do they have merit, why or why not? E.g. Local first. If you don't want to write about it but know of one, whether having merit for excitement around it or not, please post a comment simply naming it to start a topic thread - and perhaps you'll inspire someone else to share their thoughts on it. Hope this isn't against the rules, dang.